Samples of panettone sourdoughs manufactured in an industrial bakery located in Japan were investigated. The sourdough starter called mother sponge was imported from Italy and propagated continuously in Japan. According to traditional practice in Italy, panettone sourdoughs were prepared. Microflora was composed of Yeast (10⁶-10⁷cfu/g) and LAB (10⁷-10⁸cfu/g). All the fermentation process, predominant yeasts has the feature of no maltose fermentation and no growth at 37°C. Predominant LAB fermented maltose and has requirement of Tween 80 for growth. DNA-DNA hybridization data exhibited they were Candida milleri and Lactobacillus sanfranciscensis. Furthermore L. sanfranciscensis forming L-lactate was isolated from panettone sourdough. And lactate dehydrogenases took part in isomer of lactate produced by them. It was confirmed that the native microflora of the panettone mother sponge was successfully preserved in Japan.

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The polyphenol content, polyphenol oxidase (PPO) activity and pH of Norin No. 1 and Toyoshiro potatoes, representative processing potato varieties in Japan, were measured, and their effects on blackspot bruise were evaluated using multiple regression analysis. The analysis showed that among these biochemical factors, PPO activity most predominantly affects blackspot bruise. This result is useful for developing new blackspot-bruise-resistant varieties.

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The possibility of using oxidation-reduction potential (ORP) as freshness index for scallops (Pecten yessoensis) was investigated. Scallops were divided into three groups and subjected to different rearing conditions : rearing at higher-than-optimum temperatures (at 15-18°C) with aeration, rearing in seawater but without aeration, or removal from seawater and live storage in air at 10°C. The ORP and pH of the adductor muscle of live scallops during rearing were measured at regular time intervals for 24h. Then the adductor muscle in each sample was removed from the valves and stored at 0°C. Changes in ORP, K value, ATP degradation, and D-lactic acid content during storage were monitored. The results showed that live scallops had a reductive characteristic in terms of ORP, which varied between 0.16-0.19V and a pH range from 6.2-7.0. However, ORP generally increased towards a more oxidative state under all the rearing conditions tested. ORP also increased with K value and approached its maximum when K value exceeded 25%. Regardless of rearing conditions, the ORP range that indicates the reasonable freshness of scallops for sashimi was 0.166-0.215V. The postmortem ATP content was highest in the scallops reared in seawater while the fastest ATP degradation observed in the live scallops stored in air. D-lactic acid accumulation during storage was lowest in the samples reared in seawater with aeration. The absence of oxygen supply during rearing promotes enhanced ATP degradation and D-lactic accumulation.

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